It is easy to remove a Gmail account, though it does take a few steps.
- Load up Gmail on your phone by clicking the Gmail icon.
- Click the Menu button and select Accounts
- Click the Account you wish to delete
- You will see a list of your Gmail accounts, click the Menu button again, there is only one option, Account Settings.
- Scroll down to Manage Accounts
- Click on the Account you wish to delete.
- Click Remove Account
** Note: This is for deleting an "additional" or "extra" email account. The procedure is different for the default email account.
Hope this helps.